Rotary cylinder machine with reciprocating rotary piston



May 17, 1966 .1. R. M. AF ROSENSCHGLD ETAL 3,251,275

ROTARY CYLINDER MACHINE WITH RECIPROCATING ROTARY PISTON Filed March 8, 1963 '7 Sheets-Sheet 1 Fig.1

Jalm I? U MUM firmer-lo INVENTORQ May 17, 1966 J. R. M. AF ROSENSCHGLD ETAL 3,251,275

ROTARY CYLINDER MACHINE WITH RECIPROCATING ROTARY PISTON Filed March 8, 1963 7 Sheets-Sheet 2 y 1966 J. R. M. AF ROSENSCHGLD ETAL 3,251,275

ROTARY CYLINDER MACHINE WITH RECIPROCATING ROTARY PISTON 7 Sheets-Sheet 5 Filed March 8, 1963 n C D ru 4 m N S I n w? 1 Fr y 1966 J. R. M. AF ROSENSCHGLD ETAL 3,251,275

ROTARY CYLINDER MACHINE WITH RECIPROCATING ROTARY PISTON Filed March 8, 1963 7 Sheets-Sheet 4 -60 Fig.4e T38 62 INVENTOR/J;

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M y 1966 .1. R M. AF ROSENSCHCBLD ETAL 3,251,275

ROTARY CYLINDER MACHINE WITH RECIPROCATING ROTARY PISTON Filed March 8, 1963 7 Sheets-Sheet 5 Mayl7, 1966 J. R. M AF ROSENSCHGLD ETAL 3,251,275

ROTARY CYLINDER MACHINE WITH RECIPROCAT ING ROTARY PISTON Filed March 8, 1963 '7 Sheets-Sheet 6 y 7, 1966 J. R. M. AF ROSENSCHCLD ETAL 3,251,275

ROTARY CYLINDER MACHINE WITH RECIPROCATING ROTARY PISTON Filed March 8, 1963 7 Sheets-Sheet '7 Fig. 7c

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United States Patent 3,251,275 ROTARY CYLINDER MACHINE WITH RECIPRQ- CATTNG ROTARY PETUN John Rutger Munck af Rosenschiild, Saltsiobaden, Karl Gnnnar Jiirgensen, Solna, and Svein Kiartan Frimanslurid, Saltsjohaden, Sweden, assignors to Atlas Copco Aktiebolag, Nacira, Sweden, a corporation of Sweden Filed Mar. 8, 1963, Ser. No. 263,990 16 Claims. (Cl. 91-201) This invention relates to machines for compressing or expanding fluids. There is a constant demand for ma- .chines for compressing or expanding fluids and great efforts have been made to produce such machines which can be manufactured with simple or conventional methods with close tolerances at low costs and which are of a light construction and in which fluid leakage is reduced to a value which results in efficient machines. It is a further desire to produce machines of the above type which may be driven with the speeds obtained with conventional combustion or electric motors without gear transmissions. It is also desirable to provide machines in which there is no or very reduced frictional contact pressure between the moving parts. For certain purposes it is also desirable to have machines in which the working fluid is not contaminated by lubricating oil or other lubricators or cooling or sealing liquids. This is of particular importance in connection with air or gas compressors designed for delivering oil free or dry compressed air or gas. There is also a desire that the machines should be designed so that service of the machines may be kept at a minimum or may be eliminated and under all conditions can be carried out by average mechanics without special training for the machine in question. The present invention provides a machine which to a great extent meets the above demands. For the above and other purposes we provide a reciprocating machine comprising working cylinder chamber forming means including a cylinder casing and piston means reciprocable in and relative to said cylinder casing for changing the volume of one or more working cylinder chambers defined by said cylinder casing and piston means, a shaft having a longitudinal axis, a frame, means for mounting said cylinder casing and piston means in said frame for rotation or two parallel axes one of said axis being arranged for moving on a circular path so as to be coincident with the other axis in one point of said path, fluid passage means in said shaft, means for mounting said working cylinder chamber forming means and said shaft for relative rotation, and intercommunicable port means in said shaft and said working cylinder chamber forming means for the passage of fluid between said Working cylinder chamber or chambers and said fluid passage means intermittently during the relative rotation of the working cylinder chamber forming means and the shaft.

A separate feature of the invention consists in the provision of a reciprocating machine comprising working cylinder chamber forming means including a cylinder casing and piston means reciprocable in and relative to said cylinder casing for changing the volume of one or more working cylinder chambers defined by said cylinder casing and said piston means, a shaft having a longitudinal axis, fluid passage means in said shaft, means for mount ing said cylinder casing and piston means for rotation on two parallel axis, means for mounting said working cylinder chamber forming means and said shaft for relative rotation, and intercommunicable port means in said shaft and said working cylinder chamber forming means for the passage of fluid between said working cylinder chamber and said fluid passage means intermittently during the relative rotation of the working cylinder chamber forming means and the shaft.

In the accompanying drawings two embodiments of double acting single stage air compressors according to the invention are illustrated by way of example, but it should be understood that the invention may also be employed in two or multiple stage machines as well as in connection with fluid expanders such as compressed air motors or combustion motors. Naturally the machines according to the invention may be built for operation on any other compressible or expansible fluid such as gas or steam. a

In the drawings FIG. 1 is a vertical axial section of a reciprocating machine according to the invention. FIG. 2 is a cross section of the machine according to FIG. 1 on lines lI-II in FIG. 1. FIG. 3 is an end view of the machine according to FIG. 1 looking towards the right end of the machine in FIG. 1. FIGS. 4a-e are diagrammatic views similar to FIG. 2 showing the cylinder casing and piston and shaft in various positions during one revolution of the shaft. FIG. 5 is and axial longitudinal vertical section of a machine according to the invention disclosing a second embodiment in which the shaft is stationary. FIG. 6 is a cross section of the frame cylinder casing and piston and shaft of. the machine in FIG. 5 on lines VV in FIG. 5, and FIGS. 7ae are diagram.- matic views similar to FIGS. 4a-e of the machine according to FIGS. 5-6.

With reference to FIGS. 1-46 the design of the machine is as follows:

The machine consists of a frame or housing which is formed by a central generally cylindrical frame portion 1 to which a front casing 2 and a rear casing 3 are secured by means of bolts 4 engaging annular flanges 5 of the central frame portion 1. A split shaft 6, 7 is mounted in the frame by means of anti-friction bearings 8 and 9, the bearing 8 being carried in the rear casing 3 in a counter bore 10 and the bearing 9 on a hub 11 formed by a front end wall 12 of the central frame portion 1. The shaft portion 6 is mounted in the bearing 8 and the shaft portion 7 on the bearing 9 by means of a cooling fan 13 which is secured to the shaft portion 7 by means of a tapering sleeve 14 and a nut 15. The shaft portion 7 is secured to the shaft portion 6 by means of a screw threaded bolt 16 which is screwed into a screw threaded bore 17 in the shaft portion 6. An axial bore 19 is provided in the shaft portion 7, which has formed thereon a toothed gear 20 and an eccentric boss 21 of circular cross section. The shaft portion 6 may be driven by any suitable means such as an internal combustion engine or an electric motor.

A cylinder casing 22 having a straight transverse bore 23 is rotatably mounted on bearings 24 and 25 carried on excentric bosses 26, 27 on the rear frame portion 3 and the front end wall 12. The bearings 24, 25 are fitted in annular flanges 28 and 29 formed on the cylinder casing 22. The cylinder casing is provided with a cylinder head 30 at each end of the bore 23 which cylinder heads are sealed in the cylinder casing by means of O-rings 31 and held in place by circlips 32.

A double acting piston 33 is reciprocable in the cylinder bore 23 and is mounted for rotation on life-time lubricated antifriction bearings 34 fitted in a. bore 35 extending transversely into the piston 33 from the left hand side in FIG. 1. The bearings 34 are fitted on the excentric boss 21 of the shaft portion 7. The piston 33 is recessed at 36 and has formed therein a port 37 which is open to the surface of the cylindrical boss 21. The piston rotates on the boss 21 on a gravity axis which is coincident with the geometrical axis of the boss 21 and the cent-re of gravity of the piston and of the boss are on this same geometrical axis. The boss 21 has a port 38 communicating with an axial suction passage 39 in the boss 21 which opens into a cavity 58 in the piston 33. The passage 39 and the cavity 58 communicate through openings 40 in the cylinder casing and openings 41 and 42 in the central frame portion with the atmosphere. The boss 21 is provided with a second port 43 which through a'passage 44 communicates with the bore 19 in the shaft portion 7. During rotation of the shaft 6, 7 relative to the piston the ports 38 and 43 are alternatively brought into communication with the ports 37 in the piston so that the boss 21 and the piston together form inlet and outlet valve means for two working cylinder chambers formed in the bore 23 by the cylinder 22 and piston 33. The. cylinder heads 30 are formed with displacement portions 45 and 46 which fit into the recesses 36 and the ports 37 in the piston and reduce the clearance at the end of the strokes of the piston.

The toothed gear carried by the shaft portion 7 is in constant mesh with a toothed ring 47 fixed by screws 48 to the flange 28 and providing a speed transmission ratio 2:1 between the shaft 6, 7 and the cylinder casing 22 which will consequently rotate with half the number of revolutions of the shaft 6, 7. The piston 33 is provided with continuous sealing rings 49 which are held in place by rings 50 of so called self-lubricating material which guide the piston during the reciprocation in the cylinder bore 23. The rings 50 are secured to the piston by lock pins or other suitable means.

The fan 13 draws cooling air through the openings 41 into the central frame portion 1 around the cylinder casing 22 through the openings 42 and blows said cooling air through a tubular cooler 53 and openings 52 in the front casing 2. The fan 13 is provided with openings 54 disposed unsymmetrically around the fan so that the fan wheel 13 provides a counterweight which balances the boss 21 and the piston 30. A complete balancing could be obtained by providing a second counterweight on the shaft 6, 7 at the opposite side of the piston to the fan wheel 13 but such complete balance is usually unnecessary for practical purposes. The boss 21 has its center of gravity on a longitudinal axis 62 and the center of gravity of the piston 30 is on the same axis. 55 is a sliding connection for a compressed air delivery fitting 56 through which the air delivered through the bore 19 is conducted to the after cooler 53 and the discharge connection 57.

The compressor according to FIGS. 1-3 operates in the following manner, specific reference being made to the diagrammatic views FIG. 4a-e. The shaft 6, 7 of the compressor is rotatable on an axis 60, the cylinder .casing 22 on an axis 61 and the piston 33 on the axis 62.

The axis 62 is the geometrical axis of the cylindrical boss 21 and upon rotation of shaft 6, 7 the axis 62 moves parallel to itself on a circular path around the axis 60. In one point of said path the axis 62 is coincident with the axis 61 as obvious from FIG. 40. In FIG. 1 the piston 33 is in its bottom position in the cylinder casing 22 as obvious from FIG. 4a and has just completed the suction stroke in the cylinder chamber 63 and compressed air in the chamber 64 which compressed air has been delivered through the port 43 and the passages 44, 19. During the continued rotation of the shaft 6, 7 in the direction of the arrow 65 a quarter revolution the cylinder and piston make an eighths revolution to the position in FIG. 4b, in which the chamber 64 has been brought into communication with the port 38 and the suction passages whereas compression has commenced in the chamber 63.

In the position of the parts illustrated in FIG. the shaft 6, 7 and boss 21 have completed one half revolution and the cylinder and piston one quarter revolution and the port 43 is just in position where it will start to open to the chamber 63 in which compression has just been completed whereas the port 38 is still open to the chamber 64 so that the suction stroke can continue.

In FIG. 4d the shaft 6, 7 and boss 21 have completed three quarter of a revolution, whereas the cylinder and piston have completed three-eighths of a revolution. The suction stroke then still continues in the cylinder chamber 64 and the air compressed in the cylinder chamber 63 is being delivered through the port 43 and the passages 44, 19.

In FIG. 4e the shaft 6, 7 and boss 21 have completed one revolution and the cylinder 22 and piston 33 one half revolution, so that the parts are again in the same position as in FIG. 4a with the exception that the chamber 64 is now positioned on top of the piston and the chamber 63 below the piston. The suction and compression cycles above described are then repeated.

It should be observed that the cylinder casing 22 rotates on a fixed axis 61 through the centre of gravity of the cylnder casing so that the cylinder casing is com- .pletely balanced. The centre of gravity of the piston 33 and of the boss 21 are on the axis 62 and the unbalanced weight of said bodies is balanced by the fan wheel 13. All rotating masses are consequently balanced. Since frictional contact pressure between cylinder and piston is substantially avoided cylinder and piston wear will be extremely small and it is possible to operate the machine as a dry machine without the use of lubricating oil.

In the embodiment of the invention illustrated in FIGS. 5, 6 and 7a-e the machine comprises a stationary shaft 70 secured with one end in a frame 71 by means of a tapering sleeve 72 and a nut 73. The shaft 70 has an excentric boss 74 of circular cross section and a piston 75 is rotatably mounted concentrically on the boss 75 on antifr-iction bearings 76. The piston 75 is reciprocable in a bore 77 in a cylinder casing 78 which is rotatably journalled on bearings 79 carried by a rotary frame 80. The rotary frame 80 which encloses the cylinder casing is rotatably mounted in bearings 81 and 82 carried in the stationary frame 71 and on the fixed shaft 70. The rotary frame 80 is also rotatably mounted on antifriction bearings 83 carried on the free end of the fixed shaft 70 which has formed thereon a gear 84 cooperating with a synchonizing gear ring 85 provided in the cylinder casing 78 the transmission ratio of said gear ring to the gear being 2:1. The rotary frame 80 is secured to a drive shaft 86by means of a rod 87 screw threaded into the rotary frame 80 at 88. Any suitable means may be provided for driving the shaft 86.

The machine according to FIGS. 5 and 6 is provided with an admission passage 91 in the boss 74 on the shaft 70 leading from the atmosphere through admission ports 92, FIG. 6, in the cylinder casing 78, ports 93 in the rotary frame and ports 94 in the frame 71. The cylinder casing and piston form Working chambers 68, 69 communicating alternately through ports 95 in the piston with an admission port 96 and a discharge port 97 in the boss 74 of the shaft 76, said discharge port leading to a passage 98 in the shaft 70. The passage 98 communicates with a tubular cooler 99 which is cooled by air passed through the cooler by a fan 1% provided on the rotary frame 80.161 is a counterweight for counterbalancing the cylinder casing 77.

The machine according to FIG. 5 and 6 operates in substantially the same manner as the machine described in connection with FIGS. 1-4. However, the shaft 70 is fixed, the piston 75 rotates on an axis 66 which is the axis of the boss 74 of the fixed shaft 70, the cylinder casing 78 rotates on an axis 67 which moves parallel to itself around the fixed axis 59 of shaft 70 on a circular path which in one point of the path is coincident with the axis 66, FIG. 70. The various positions taken by the cylinder casing 78 and piston 75 during one half revolution of the cylinder casing 78 and one revolution of the rotary frame 86 is illustrated in FIGS. 7ae, rotation being in the direction of arrow 102.

It should be understood that the machines described hereinabove are only examples and may be varied in different ways within the scope of the claims. For instance, the machine illustrated in FIGS. 1-4e may be driven with high a speed motor coupled to the shaft 6, 7 or with a fifty percent slower motor driving on the cylinder casing 22. The machine according to FIGS. 1-3 and 5-6 may also be modified in that the piston and cylinder casing may change place with regard to the boss 21 or 74, since it is obvious that it does not make much difference if the piston means or the cylinder means operate as the rotary valve means which cooperate with boss 21 or 74 and controls the ports 38 and 43 or 96, 97. Furthermore, in connection with compressors the discharge port may be in the shaft and the admission ports to the working cylinder chambers may be ports, in the cylinder or piston controlled by automatic suction valves in the cylinder head or piston top.

What we claim is:

1. A reciprocating machine comprising working cylinder chamber forming means including a cylinder casing and piston means reciprocable in and relative to said cylinder casing for changing the volume of at least one working cylinder chamber defined by said cylinder casing and piston means, a shaft having a longitudinal axis, a frame,

means for mounting said cylinder casing and piston means in said frame for rotation on two parallel axes, one of said axis being arranged for moving on a circular path so as to be coincident with the other axis in one point of said path, fluid passage means in said shaft, means for mounting said working cylinder chamber forming means and said shaft for relative rotation, and intercommunicable port means in said shaft and said working cylinder chamber forming mean for the passage of fluid between said working cylinder chamber and said fluid passage means intermittently during the relative rotation of the working cylinder chamber forming means and the shaft.

2. A reciprocating machine comprising working cylinder chamber forming means including a cylinder casing and piston means reciprocable in and relative to said cylinder casing for changing the volume of working cylinder chambers defined by said cylinder casing and said piston means, a shaft having a longitudinal axis, fluid passage means in said shaft, means for mounting said cylinder casing and piston means for rotation on parallel axes, means for mounting said working cylinder chamber forming means and said shaft for relative rotation toothed gear means drivingly coupling said shaft to said working cylinder chamber forming means with a speed transmission ratio of 2:1, and intercommunicable port means in said shaft and said working cylinder chamber means for the passage of fluid between said working cylinder chambers and said fluid passage means intermittently during the relative r-otaton of the working cylinder chamber forming means and the shaft.

3. A reciprocating machine comprising straight working cylinder chamber forming means including a cylinder casing and piston means rectilinearly reciprocable in and relative to said cylinder casing for changing the volume of working cylinder chambers defined by said cylinder casing and said piston means, a frame, a shaft carried by said frame and having a longitudinal axis, a first fluid passage means extending longitudinally in said shaft, a second separate fluid passage means extending longitudinally in the shaft, means for mounting the cylinder casing and piston means for rotation on parallel axes, means for mounting said working cylinder chamber forming means and the shaft for relative rotation, toothed gear means drivingly coupling said shaft to said working cylinder chamber forming means with a speed transmission ratio of 2:1 and intercommunicable port means in the shaft and the working cylinder chamber forming means for the passage of fluid between said working cylinder chambers and said first and second passages during the relative rotation of the working cylinder chamber forming means and the shaft for selectively admitting working fluid through the first pass-age and discharging it through the second passage.

4. A reciprocating machine comprising working cylinder chamber forming means including a rotatable cylinder casing and rotatable piston means reciprocable in and relative to said cylinder casing for changing the volume of working cylinder chambers defined by said cylinder casing and said piston means, a frame, a shaft carried by said frame and having a longitudinal axis, toothed gear means drivingly coupling said shaft to said working cylinder forming means with a speed transmission ratio of 2:1, an excentric cylindrical boss of circular cross sect-ion on said shaft, and bearing means for rotatably mounting said piston means on said boss substantially in the plane of rotation of said cylinder casing.

5. A reciprocating machine comprising working cylinder chamber forming means including a rotatable cylinder casing and rotatable piston means reciprocable in and relative to said cylinder casing for changing the volume of working cylinder chambers defined by said cylinder casing and said piston means, a frame, a shaft rotatably mounted in said frame and having a longitudinal axis, toothed gear means for transmitting rotational movement between said shaft and said casing and said piston means, said casing and piston means rotating excentrically with respect to said shaft, and bearing means for mounting said casing on each side of its plane of rotation.

6. A reciprocating machine comprising working cylinder chamber forming means including a rotatable cylinder casing and rotatable piston means reciprocable in and relative to said cylinder casing for changing the volume of working cylinder chambers defined by said cylinder casing and piston means, a frame, a shaft mounted for rotation in said frame in bearing means at each side of the plane of rotation of said casing and piston means, and a toothed gear transmission between said working cylinder chamber-forming means and said rotatable piston means having a transmission ratio of 2:1.

7. A reciprocating machine comprising working cylinder chamber forming means including a rotatable cylinder casing and rotatable piston means reciprocable in and relative to said cylinder casing for changing the volume of working cylinder chambers defined by said cylinder casing and piston means, a frame, a shaft having a longitiudinal axis and axially extending inlet and outlet passages, toothed gear means drivingly coupling said shaft to said working cylinder chamber forming means with a speed transmission ratio of 2:1, rotary valve means in said shaft having ports communicating with said passages, respectively, and ports in said working cylinder chamber forming means communicable with said shaft port alternately to admit fluid to the working cylinder chambers and to discharge fluid from said working cylinder chambers, respectively.

8. A reciprocating machine comprising working cylinder chamber forming means including a rotatable cylinder casting and rotatable piston means reciprocable in and relative to said cylinder casing for changing the volume of working cylinder chambers defined by said cylinder casing and piston means, a frame, a shaft having a longitudinal axis, means for mounting said cylinder casing and piston means for rotation excentrically relative to said shaft on axes parallel to said axis of the shaft, fluid passage means in the shaft, a recess in the top end of said piston means, a displacement body in said cylinder means arranged to substantially fill out said recess in the piston 'means when the cylinder and piston means are moved 9. A reciprocating machine according to claim 2 having a frame and in which said shaft is mounted for rotation in bearings in said frame and extends through said cylinder casing and piston means.

10. A reciprocating machine according to claim 2, having a stationary frame in which said shaft is carried and fixed, a rotary frame mounted for rotation on said shaft and said stationary frame, means for mounting said cylinder casing for rotation on said rotary frame, and means for mounting said piston means for rotation on said fixed shaft on an axis parallel to and off-set to the axis of rotation of said rotary frame.

11. A reciprocating machine according to claim 9, in which means are provided on the shaft for drivingly connecting said shaft to a motor.

12. A reciprocating machine according to claim 10, in which means are provided on the rotary frame fordrivingly connecting the rotary frame to a motor.

13. A reciprocating machine according to claim 9, in which an eccentric cylindrical boss of circular cross section is provided on the shaft and an opening in the cylinder casing for inserting said boss transversely into the cylinder casing.

14. A reciprocating machine comprising working cylinder chamber forming means including a rotatable cylinder casing and rotatable piston means reciprocable in and relative to said cylinder casing for changing the volume of working cylinder chambers defined by said casing and said piston means, a frame, a shaft carried by said frame and having a longitudinal axis and mounted'for rotation in said frame, an eccentric cylindrical boss of circular cross section on said shaft, bearing means for mounting said piston for rotation on said boss, and counterweight means mounted on said shaft for balancing said boss and said piston means.

15. A reciprocating machine comprising working cylinred chamber forming means including a rotatable cylinder casing and rotatable piston means reciprocable in and relative to said cylinder casing for changing the volume of working cylinder chambers defined by said cylinder casing and said piston means, a stationary frame, a fixed shaft carried by said stationary frame having a l on gitudinal axis, a rotary frame mounted for rotation on the stationary frame on said longitudinal axis, an eccentric cylindrical boss of circular cross section on said fixed shaft, bearing means for mounting said piston for rotation on said boss, bearing means for mounting said cylinder casing for rotation on said rotary frame on an axis offset to and parallel with the axis of rotation of the rotary frame, and counter weight means on said rotary frame for balancing said cylinder casing.

16. A reciprocating machine according to claim 1 in which a toothed gear transmission having a transmission rat o of 2:1 is provided between said cylinder casing and said piston means.

References Cited by the Examiner UNITED STATES PATENTS 683,834 10/190] Beckfield 91-204 772,353 10/1904 Halsey 91-201 1,853,391 4/1932 Westman et al. 103-42 X 1,897,190 2/1933' Eysten 103-160 2,087,816 7/1937 Saussard et al 103-160 2,258,379 10/1941 Estey 103-16O SAMUEL LEINE, Primary Examiner.

FRED E. ENGELTHALER, Examiner. 

1. A RECIPROCATING MACHINE COMPRISING WORKING CYLINDER CHAMBER FORMING MEANS INCLUDING A CYLINDER CASING AND PISTON MEANS RECIPROCABLE IN AND RELATIVE TO SAID CYLINDER CASING FOR CHANGING THE VOLUME OF AT LEAST ONE WORKING CYLINDER CHAMBER DEFINED BY SAID CYLINDER CASING AND PISTON MEANS, A SHAFT HAVING A LONGITUDINAL AXIS, A FRAME, MEAND FOR MOUNTING SAID CYLINDER CASING AND PISTON MEANS IN SAID FRAME FOR ROTATION ON TWO PARALLEL AXES, ONE OF SAID AXIS BEING ARRANGED FOR MOVING ON A CIRCULAR PATH SO AS TO BE COINCIDENT WITH THE OTHER AXIS IN ONE POINT MEANS SAID PATH, FLUID PASSAGE MEANS IN SAID SHAFT, MEANS FOR MOUNTING SAID WORKING CYLINDER CHAMBER FORMING MEANS AND SAID SHAFT FOR RELATIVE ROTATION, ND INTERCOMMUNICABLE PORT MEANS IN SAID SHAFT AND SAID WORKING CYLINDER CHAMBER FORMING MEAN FOR THE PASSAGE OF FLUID BETWEEN SAID WORKING CYLINDER CHAMBER AND SAID FLUID PASSAGE MEANS INTERMITTENTLY DURING THE RELATIVE ROTATION OF THE WORKING CYLINDER CHAMBER FORMING MEANS AND THE SHAFT. 